Mattgouras, The engine list that he has linked has many errors in it- there are 2 listings for the '67 YH code on that list. They have it listed as a 400 and the 428 HO. Neither are correct.
I checked the first three resources that came to mind after seeing his ebay questions. I checked the engine code databases on Wallace Racing and Classical Pontiac and also checked the engine code listings in Standard Catalog of Pontiac and all of them agreed- 360 horse 428.
I'm not trying to be a ball-buster, just correct a mistake.
I'd love to see a 428 HO wagon, that'd be really cool.
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1966 GTO
1969 Lemans Convertible- F.A.S.T. legal family cruiser. 12.59 on G70-14 Polyglas tires. 1.78 60'
1969 Bonneville Safari- cross country family cruiser. .
1979 Trans Am 400, 4-speed, 4 wheel disc.
View from the drivers seat racing down Atco Raceway-
http://www.youtube.com/watch?v=GhYDMdOEC7A
Ride along in the other lane-
http://www.youtube.com/watch?v=mIzgpLtF_uw